Currently, as a 3D image viewing mode, generally, there is a mode (hereinafter, referred to as a two-viewpoint mode) in which two-viewpoint images alternately displayed are seen by wearing glasses of which a left-eye shutter is open at the time of displaying one image out of two-viewpoint images, and a right-eye shutter is open at the time of displaying the other image.
However, in such a two-viewpoint mode, a viewer needs to purchase glasses in addition to a 3D image display device, and accordingly, the viewer's willingness to buy reduces. In addition, since a viewer needs to wear glasses for viewing, it annoys the viewer. Accordingly, a demand for a viewing mode (hereinafter, referred to as a multi-viewpoint mode) increases in which a 3D image can be viewed without wearing glasses.
In the multi-viewpoint mode, multi-viewpoint images are displayed such that a viewable angle is different for each viewpoint, and, a 3D image can be seen by a viewer viewing images of arbitrary two viewpoints with left and right eyes without wearing glasses.
A display device that provides viewing of a multi-viewpoint mode, for example, generates multi-viewpoint images for a multi-viewpoint mode based on images of two viewpoints for a two-viewpoint mode and displays the generated multi-viewpoint images. More specifically, the display device acquires parallax (depth) of two-viewpoint images for a two-viewpoint mode using an image parallax estimating technology (Depth Estimation). Then, the display device generates a synthesized image of multi-viewpoint images adjacent to a viewpoint corresponding to the images of two viewpoints for a two-viewpoint mode using a multi-viewpoint image generating technology (View Generation) using the parallax between images of two viewpoints and a synthesis technology (View Synthesis) and displays the synthesized image.
Existing encoding modes include an advanced video coding (AVC) mode and a multi-view video coding (MVC) mode.
FIG. 1 is a diagram that illustrates an example of an encoding device that encodes two-viewpoint images in the MVC mode and multiplexes the encoded images.
The encoding device 10 illustrated in FIG. 1 is configured by an imaging unit 11A, an imaging unit 11B, an MVC encoder 12, and a multiplexing unit 13.
The imaging unit 11A captures an image A of a predetermined viewpoint and supplies the captured image to the MVC encoder 12. In addition, the imaging unit 11B captures an image B of a viewpoint that is different from that of the image A and supplies the captured image to the MVC encoder 12. The MVC encoder 12 performs encoding in accordance with the MVC mode with the image A supplied from the imaging unit 11A set as a base image and the image B supplied from the imaging unit 11B set as a dependent image. The MVC encoder 12 supplies the images A and B after the encoding to the multiplexing unit 13. The multiplexing unit 13 generates a first TS (transport stream) (hereinafter, referred to as TS1) based on the image A after the encoding, generates a second TS (hereinafter, referred to as TS2) based on the image B after the encoding, and multiplexes the TS1 and TS2.
The multiplexed TS1 and TS2 are separated by a decoding device, and the images A and B after the encoding are decoded in accordance with a mode that corresponds to the MVC mode. Then, the images A and B that are acquired as a result of the decoding are alternately displayed. At this time, a viewer, for example, wears glasses of which the left-eye shutter is open at the time of displaying the image A and of which the right-eye shutter is open at the time of displaying the image B, views the image A only with the left eye, and views the image B only with the right eye. In this way, the viewer can see a 3D image. In a case where a 2D image is desired to be displayed, only the image A is displayed.
Meanwhile, a mode for encoding a multi-viewpoint image has also been devised (for example, see Patent Document 1).